-LRB- CNN -RRB- -- Based on Mick Jagger 's serious expression and Keith Richards ' focused stare , it was clear the pressure was on .

It was the summer of 1972 , and the Rolling Stones were on their American concert tour for their acclaimed `` Exile on Main Street '' album . But when they were not onstage and rocking out with their fans , they were hard at work remixing tracks at the Sunset Sound studio in Hollywood .

It was a heady time filled with parties and recording sessions and only one person was there to capture it all intimately -- famed music photographer Jim Marshall , who was covering the tour for Life magazine .

Now the estate of Marshall is releasing some of the never-before-seen photos of the band in a new book `` The Rolling Stones 1972 '' -LRB- Chronicle Books -RRB- , out on August 15 . There will also be a show at New York 's Steven Kasher Gallery from July 5 to September 8 , and an exhibit at EMP Museum in Seattle , opening on July 14 . Some of these frames are being displayed exclusively on the CNN Photos blog . The release could n't have had better timing as the Rolling Stones recently announced plans to mark their 50th anniversary this year .

Amelia Davis , a photographer who worked as Marshall 's assistant , is the sole owner of Jim Marshall Photography . -LRB- Marshall died in 2010 . -RRB- Working with Marshall to archive his work allowed her to listen to Marshall 's many stories and delve into his memories . Davis told CNN that what made Marshall 's shots unique was that he always demanded total access to the rock stars .

`` He really was everywhere with the musicians on the tour bus or offstage , '' Davis said . `` He always had his camera with him . People ignored the camera in a sense . It was an extension of him . He had the ability to be a fly on the wall . ''

Marshall 's ability to camouflage without disturbing the band 's dynamic also allowed him to experience the touring life of the Rolling Stones , Davis said .

`` It really set the precedent for the rock star concert tour , '' she said . `` They had their own plane , lots of drugs , lots of alcohol . It was just crazy . There was a lot going on . ''

Davis said that Marshall 's strong personality , fierce passion for music and his drive to get the best pictures while maintaining a sense of camaraderie made him relatable to musicians such as Richards .

`` He was their friend , '' she said . `` He partied with them . He had their trust . As Keith said in the foreword of the book , on the tour he was like another Rolling Stone . ''

But Marshall most enjoyed capturing those quiet moments , when the musicians took off their performer masks and were just themselves , she said . One only has to look at photos of Jagger onstage and off it to see the different personas .

`` Mick was very business-oriented , '' Davis said . `` Mick was much more serious than Keith . That 's what a lot of people do n't realize is that he was the businessman of the band . ''

Davis said that while Marshall spent a short time following the Stones , it was enough to create a bond with some of the members , especially Richards .

But the most important task for Marshall during his career , whether it was the Beatles ' final concert in 1966 or Jimi Hendrix 's performance during the Monterey Pop Festival in 1967 , was to capture the feeling of music , a task that could seem quite impossible .

`` Jim was always trying to show the true face of whatever he photographed , '' Davis said . `` He shattered stereotypes of what rock stars are supposed to look like . He said , ' I was a historian with a camera and I did n't know it . ' He was photographing pieces of history . ''

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Jim Marshall photographed the Rolling Stones during their American concert tour in 1972

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Marshall 's estate shares unseen photos in a new book , gallery show and museum exhibit

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Some of these frames are being exclusively displayed on CNN 's photo blog